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1.
Detailed characteristics of adolescent suicides (aged 13–19 years) with adjustment disorders (AD) (N=11) or no psychiatric diagnosis (N=3) in a nationwide adolescent suicide population (N=53) from Finland are presented. The data were collected in a psychological autopsy study of all suicides in Finland (N=1397) during a 12-month period in 1987–1988. Data collection included thorough interviews with the victims' family members and professionals, and information from official records. All the suicides with AD or no diagnosis were males. Most of these victims used highly lethal suicide methods. Previous psychiatric treatment and previous suicide attempts were rare. They were seldom under the influence of alcohol when committing suicide. The process leading to suicide seemed to be of relatively short duration. According to informant reports, withdrawn or narcissistic individual characteristics predominated in many cases. Psychosocial stressors preceding suicide often involved interpersonal losses or conflicts. Talking of suicidal intentions prior to the act was common, indicating the need to take seriously all adolescents' expressions of intended suicide, even in the absence of explicit psychopathology.
Zusammenfassung Es werden detaiilierte Beschreibungen von Selbst-morden im Jugendalter, verbunden mit Anpassungsstörungen (N=11) oder keiner psychiatrischen Diagnose (N=3) vorgestellt. Diese stammten aus der Gesamtheit aller jugendlichen Selbstmörder (N=53) aus Finnland. Die Daten wurden in einer psychologischen Obduktionsstudie aller Selbstmörder Finnlands (N=1397) während eines einjährigen Zeitraumes zwischen 1987 und 1988 gesammelt. Die Datenerhebung umfaßte ausgiebige Interviews mit den Familienmitgliedern, beteiligten Fachkräften und Informationen von offizieller Seite. Die Selbstmörder mit Anpassungstörungen oder keiner Diagnose waren alle männlich. Die meisten dieser Opfer benützten sehr letale Suizidmethoden. Vorangegangene psychiatrische Behandlungen und Selbstmordversuche waren selten. Sie standen nur selten unter dem Enfluß von Alkohol, als der Selbstmord vollzogen wurde. Der Prozeß, der zu dem Suizid führte, schien von relativ kurzer Dauer zu sein. Entsprechend den Angaben der Informanden prädominierten in vielen Fällen zurückgezogene oder narzißtische Persönlichkeitsmerkmale. Psychosoziale Stressoren, die dem Suizid vorangingen, umfaßten interpersonelle Verluste oder Konflikte. Häufig wurde über die Suizidabsichten vor der Tat gesprochen. Dies verdeutlicht die Notwendigkeit, alle Suizidäußerungen von Jugendlichen ernstzunehmen, selbst dann, wenn eine explizite Psychopathologie fehlt.

Résumé Les caractéristiques détaillées de suicides d'adolescents (âgés de 13 à 19 ans) avec troubles avec l'adaptation (AD) (N=11) ou l'absence de diagnostic psychiatrique (N=3) sur une population de suicides d'adolescents s'étendant sur l'ensemble du pays (N=53), la Finlande sont présentées. Les faits ont été collectés dans le cadre d'une étude d'autopsie psychologique de tous les suicides en Finlande (N=1397) pendant une période de 12 mois 1987–1988. Le recueil des faits incluait des interviews avec les membres de la famille des victimes et les professionels ainsi que les informations provenant de documents officiels. Tous les suicides avec un trouble de l'adaptation ou sans diagnostic étaient masculins. La plupart de ces victimes utilisait des méthodes hautement mortelles. Les traitements psychiatriques précédents et les tentatives précédentes de suicides étaient rares. Ils étaient rarement sous l'influence de l'alcool quand ils ont commis les suicides. Le processus conduisant au suicide semblait être de durée relativement brève. Selon les rapports d'information, une attitude de retrait ou des caractéristiques individuelles de retrait prédominaient dans la majorité des cas. Les facteurs de stress psycho-sociaux précédent le suicide impliquaient souvent des pertes inter-personnelles ou des conflits. Parler du désir du suicide devant le passage à l'acte était habituel indiquant la nécessité de prendre au sérieux tous les adolescents exprimant le désir de suicide, même en l'absence d'une psychopathologie explicite.
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Human rhinoviruses (HRV) have been shown to be the major causative agent for mild respiratory infections, but also associated with more serious diseases, such as acute otitis media and pneumonia in children, and asthma. Despite the economical and medical importance of HRV, little is known about the circulation and genetic diversity of HRV during a given season. The aim of this study was to genetically characterize HRV strains causing acute respiratory infections in a cohort of small children during a 2 years follow-up time. Genetic relationships between 61 HRV field isolates were studied using partial genomic sequencing in the VP4/VP2 region (420 nt) and phylogenetic analysis of these sequences. Sequences from the clinical isolates clustered in the two previously known phylogenetic clades, the designated genetic group 2 (including HRV 14) being more predominant. The maximum genetic variation within group 1 was 32.3% and within group 2 it was 32.7%. Several distinct clusters could be observed, some of which were strictly seasonal, whereas some other variants were detected during several seasons. The results of this study show striking genetic diversity of the HRV strains circulating in a given community during a short time.  相似文献   
4.
Dynamic differential calorimetry measurements of poly(oxy-2,6-dimethyl-1,4-phenylene) and poly(oxy-2,6-dimethoxy-1,4-phenylene) at the glass transition range show that both the location and the shape of the curves are dependent upon the thermal history of the samples. The shape of the curves can be explained by means of the hole theory. The increase of length of side chain groups causes the glass transition to move to lower temperature which is attributed to the flexibility of the side chain substituents as well as to the decreased intermolecular effects. The apparent activation energies of the glass transition in poly(oxy-2,6-dimethyl-1,4-phenylene) and poly(oxy-2,6-dimethoxy-1,4-phenylene) follow the WILLIAMS -LANDEL -FERRY equation approaching the empirical curve for sterically restricted bulkly polymers devised by LEWIS .  相似文献   
5.
Bacteriological findings in 339 sinus secretions obtained by puncture were investigated in 238 young adult patients with acute maxillary sinusitis. Aerobic and anaerobic cultures were performed immediately. A total of 76% of the secretions were positive. The most common pathogens isolated were Haemophilus influenzae (50%), Streptococcus pneumoniae (19%), Streptococcus pyogenes (5%), and Branhamella catarrhalis (2%). Coagulase-negative staphylococci and Staphylococcus aureus were isolated in 8 and 1% of the specimens, respectively. The staphylococci were almost invariably present in low numbers and, therefore, probably represented nasal contamination. Other aerobic species were found only occasionally. Anaerobes were isolated in 5% of the secretions. In one-half of these, a low concentration of Propionibacterium acnes was the sole anaerobe that was found, and it was usually mixed with a facultative organism (suggestive of contamination with nasal flora). Only 2% of the sinuses were considered to have true anaerobic infections (high concentrations of several species typical of anaerobic infection), indicating that anaerobes are not a significant cause of acute maxillary sinusitis in a young adult population. The high recovery of H. influenzae in this study indicates that aminopenicillins may be more appropriate choice than conventional penicillin in the antimicrobial therapy of acute maxillary sinusitis (only 2 of 168 H. influenzae strains produced beta-lactamase).  相似文献   
6.
Dose planning in boron neutron capture therapy (BNCT) is a complex problem and requires sophisticated numerical methods. In the framework of the Finnish BNCT project, new deterministic three-dimensional radiation transport code MultiTrans SP3 has been developed at VTT Chemical Technology, based on a novel application of the tree multigrid technique. To test the applicability of this new code in a realistic BNCT dose planning problem, cylindrical PMMA (polymethyl-methacrylate) phantom was chosen as a benchmark case. It is a convenient benchmark, as it has been modeled by several different codes, including well-known DORT and MCNP. Extensive measured data also exist. In this paper, a comparison of the new MultiTrans SP3 code with other methods is presented for the PMMA phantom case. Results show that the total neutron dose rate to ICRU adult brain calculated by the MultiTrans SP3 code differs less than 4% in 2 cm depth in phantom (in thermal maximum) from the DORT calculation. Results also show that the calculated 197Au(n,gamma) and 55Mn(n,gamma) reaction rates in 2 cm depth in phantom differ less than 4% and 1% from the measured values, respectively. However, the photon dose calculated by the MultiTrans SP3 code seems to be incorrect in this PMMA phantom case, which requires further studying. As expected, the deterministic MultiTrans SP3 code is over an order of magnitude faster than stochastic Monte Carlo codes (with similar resolution), thus providing a very efficient tool for BNCT dose planning.  相似文献   
7.
The quantification of a BNCT 10B-carrier, L-p-boronophenylalanine-fructose complex (BPA-F), was evaluated using 1H magnetic resonance spectroscopy (1H MRS) with phantoms at 1.5 and 3.0 T. For proper quantification, relaxation times T1 and T2 are needed. While T1 is relatively easy to determine, the determination of T2 of a coupled spin system of aromatic protons of BPA is not straightforward with standard MRS sequences. In addition, an uncoupled concentration reference for aromatic protons of BPA must be used with caution. In order to determine T2, the response of an aromatic proton spin system to the MRS sequence PRESS with various echo times was calculated and the product of the response curve with exponential decay was fitted to the measured intensities. Furthermore, the response curve can be used to correct the intensities, when an uncoupled resonance is used as a concentration reference. BPA was quantified using both phantom replacement and internal water referencing methods with accuracies of +/- 5% and +/- 15%. Our phantom results suggest that in vivo studies on BPA concentration determination will be feasible.  相似文献   
8.
BACKGROUND: We report data on 1-year prevalence and comorbidity of depression, related impairment, treatment need, and psychiatric treatment among young adults. METHODS: A sample of young urban adults (n=245) mean age 21.8 years was screened from a baseline population of 706 high-school students and given a semistructured clinical interview to evaluate 12-month prevalence of depression, psychosocial functioning according to DSM-IV GAF scale, need for psychiatric treatment, and use of mental health services. RESULTS: One in 10 young adults suffered from depression with associated psychosocial impairment, the female-to-male-ratio being approximately 2:1. Most depressive disorders were comorbid with other DSM-IV disorders, depression usually occurring secondary to other disorders. Comorbidity was related to impairment, treatment need, and treatment contacts. Less than half of the depressed young adults had ever contacted mental health services, and less than one-third reported treatment contacts during the index episode. Males were less likely than females to report previous treatment contacts or intention to refer to mental health services for their problems, but treatment contacts during the index episode were reported equally often by both sexes. CONCLUSIONS: A minority of the severely depressed young adults with associated impairment had sought treatment. Except for subjects with dysthymia, no gender difference emerged in treatment contact rates during the 12-month depression episode. Comorbidity showed important clinical implications by its relation to severity of depression and treatment contacts.  相似文献   
9.
Location on chromosome 15 of the gene defect causing Marfan syndrome   总被引:22,自引:0,他引:22  
BACKGROUND. Marfan syndrome, "the founding member" of the heritable disorders of connective tissue, is a common autosomal dominant disorder with highly variable clinical manifestations in the skeletal, ocular, and cardiovascular systems. The fundamental defect leading to this disease has escaped definition despite decades of research efforts by several groups of investigators. METHODS AND RESULTS. Using linkage analyses with polymorphic markers of the human genome, we mapped the genetic defect to chromosome 15 in five families with Marfan syndrome. With three polymorphic markers we obtained definitive proof of linkage in these families (lod score = 3.92, theta = 0.0 +/- 0.11). The most probable location of the gene for the disease is currently D15S45 (lod score = 3.32, theta = 0.0 +/- 0.12). CONCLUSIONS. The chromosomal localization of the mutation in Marfan syndrome is a first step toward the isolation and characterization of the defective gene and serves as a diagnostic test in families in which cosegregation of these markers with the disease has been confirmed.  相似文献   
10.
Nine sawmill workers were divided into two groups according to their exposure to 2-ethylhexanoic acid, (EHA), a pesticide which has replaced the older pentochlorophenol. The men with lower exposure excreted 30±10 nmol EHA/mmol creatinine (mean ±SD,n=4) in urine samples taken after the workshift, whereas men with higher exposure excreted 1.8±1.6 mol EHA/mmol creatinine (mean±SD,n=5,p<0.01). The urinary ornithine and arginine concentrations were at the lower exposure 1.4±0.4 and 1.5±0.8 mol/mmol creatinine, respectively (mean±SD,n=4), and they increased significantly (p<0.01) to 4.5±2.5 and 3.2±1.5mol/mmol (mean±SD,n=5), respectively, at the higher exposure. This might have been caused by the inhibitory effect of EHA on urea synthesis which was partially compensated for by elevated arginine and ornithine concentrations to drive the urea cycle more efficiently.  相似文献   
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